Biomedical subjects

F Li

Publications and source records attributed to F Li.

At least 127 records · Page 7Linked to original sources

PubMed2001

Benidipine dilates both pre- and post-glomerular arteriole in the canine kidney.

The aim of the present study was to determine the effects of benidipine on renal function and whether benidipine may dilate the efferent arteriole as well as the afferent arteriole of the canine kidney. The effects of benidipine on the renal segmental vascular resistance were estimated using Gomez's formula with some modification. The renal hemodynamic action of benidipine was also compared with that of amlodipine. Intrarenal arterial injection of benidipine at a dose of 3 microg/kg resulted in a significant increase in renal blood flow (RBF), urine flow and urinary excretion of sodium, but not in glomerular filtration rate (GFR). Amlodipine at a dose of 300 microg/kg also increased RBF, urine flow and urinary excretion of sodium to a significant degree equivalent to that by benidipine. However, in contrast to benidipine, amlodipine significantly increased GFR. After the administration of benidipine, autoregulation of RBF and GFR was relatively maintained and the renal perfusion pressure (RPP)-RBF relation shifted upward; that is, RBFs at 75 and 50 mmHg were maintained at a higher level than those of the control. In contrast to benidipine, amlodipine diminished the autoregulation of RBF and GFR. RBFs at 75 and 50 mmHg were not different from those of the control. The afferent and efferent arteriolar resistance (Ra and Re) were calculated based on the RPP-RBF and RPP-GFR relations. Benidipine reduced both Ra and Re, but amlodipine selectively reduced Ra. Benidipine increased RBF but not GFR via the dilation of both afferent and efferent arterioles. Thus, benidipine has unique renal hemodynamic actions which differ from those by most calcium antagonists.

Animals↗

PubMed2001

Examining developmental trajectories in adolescent alcohol use using piecewise growth mixture modeling analysis.

OBJECTIVE: This study examined issues of heterogeneity in multiple stage development as it corresponds to qualitatively different developmental trajectories in alcohol use during adolescence. METHOD: Using a piecewise growth mixture modeling methodology, a two-piece growth model capturing growth trajectories in adolescent alcohol use from middle school (Grades 6 through 8) to high school (Grades 9 through 12) was examined (N = 179; 54% male). It was hypothesized that (1) two stages of alcohol use development with varying trajectories would exist in these data (the first corresponding to development during middle school, followed by a second stage of continuing growth during high school) and (2) there would be multiple growth trajectories (subgroups) of alcohol use in the stage-wise development, with varying effects in initial alcohol use and growth rates of alcohol use. RESULTS: Results indicated the tenability of the two-piece growth model of alcohol use with heterogeneity in the population comprising two distinct latent developmental trajectory classes. Class 1, with a high initial status of alcohol use at Grade 6, showed an upward increase in trajectory only during high school. Class 2, with a low initial status of alcohol use at Grade 6, showed a linear increase in middle school with a second growth spurt at high school entry and continuity in growth throughout the high school years. Analyses, incorporating time-invariate covariates, indicated varying influences of gender, early levels of deviant behavior, family structure (single vs two parent), peer encouragement and parent disapproval of alcohol use, and adolescent deviant behavior upon high school entry, on the two trajectory classes. Results also showed effects of the identified trajectories, with varying magnitudes, on later substance use in young adulthood, with Class 1 showing the strongest continuity in later substance use. CONCLUSIONS: Findings suggest heterogenous development of alcohol use in the adolescent population, associated with varying background and covariate influences. In addition, this heterogeneity is linked to alcohol and other substance use in young adulthood.

Adolescent↗

PubMed2001

Reduction of ischemic damage by application of insulin-like growth factor-1 in rat brain after transient ischemia.

In order to investigate a possible effect of insulin-like growth factor-1 (IGF-1) on ischemic brain injury, IGF-1 was applied topically on the brain surface of reperfused rat brain after 60 min of transient middle cerebral artery occlusion. In contrast to the cases treated with vehicle, the infarct volume was greatly reduced at 24 h of reperfusion by the treatment with IGF-1. Immunohistochemical analysis in the middle cerebral artery territory showed that Caspase-3 staining was markedly reduced in the cases with IGF-1 treatment, but 72-kDa heat shock protein staining remained almost unchanged. The present results suggest that treatment with IGF-1 exerts a significant effect on ameliorating brain injury after transient focal brain ischemia. Moreover, this effect is greatly associated with the reduction of Caspase-3 staining, but is only minimally associated with a decreasd stress response at the cellular level.

Animals↗

PubMed2001

High-resolution CT analysis of small peripheral lung adenocarcinomas revealed on screening helical CT.

OBJECTIVE: The purpose of this study was to determine the correlation between high-resolution CT morphologic features of small peripheral lung adenocarcinomas and tumor growth patterns. MATERIALS AND METHODS: We examined high-resolution CT morphologic features of 59 small, surgically resected peripheral lung adenocarcinomas (diameter, 6-20 mm) that were detected on screening for lung cancer using low-dose helical CT. Among these adenocarcinomas, 14 (24%) were visible and 45 (76%) were invisible on conventional chest radiography. The correlation between high-resolution CT morphologic features and tumor growth patterns was analyzed. RESULTS: Sixteen (94%) of 17 type A (Noguchi's classification) adenocarcinomas appeared as nodules of pure ground-glass attenuation (high-resolution CT type I). Ten (71%) of 14 type B tumors appeared as heterogeneous, low-attenuation nodules (type II). Seven (29%) of 24 type C tumors appeared as nodules with ground-glass attenuation in the periphery and a high-density central zone (type III), and 12 (50%) of 24 type C tumors appeared as homogeneous nodules with soft-tissue density (type IV). Among tumors with a replacement growth pattern, the size and CT values of type C tumors were larger than those of type A or type B tumors (p < 0.05), whereas the percentage of ground-glass attenuation and retained air space in type C tumors was smaller than those in type A or type B tumors (p < 0.01). All (100%) four type D tumors appeared to be homogeneous nodules with soft-tissue density (type IV). CONCLUSION: Small peripheral lung adenocarcinomas shown on CT exhibit four high-resolution CT patterns that corresponded to the histopathologic findings of different tumor growth patterns.

Adenocarcinoma↗

PubMed2001

Dominantly inherited familial myasthenia gravis as a separate genetic entity without involvement of defined candidate gene loci.

Myasthenia gravis (MG) is a sporadic autoimmune disorder affecting neuromuscular transmission. Very rarely autoimmune myasthenia gravis may be inherited within a family. We present here the genetic analysis of a Hungarian family where nine members from two generations are affected by myasthenia gravis. Genetic characterisation of this unique Hungarian family using linkage analysis and mutation screening excludes the involvement of defined candidate gene loci. These findings point to familial MG as a separate genetic entity. Identification of the underlying genetic defect in this family may greatly enhance our understanding of the pathogenesis of myasthenia gravis.

Adolescent↗

PubMed2001

Study of iron metabolism abnormality in the hepatocyte damage of hepatitis B.

OBJECTIVE: To study the effect of iron metabolism on patients with hepatitis B. METHODS: Hemoglobin (Hb), serum ferritin (SF), transferritin (TRF), serum iron (SI), and total iron binding capacity (TIBC) were detected in 103 patients with hepatitis B and 20 healthy adults. RESULTS: The severer the hepatocyte damage was, the higher the SF, SI and the lower the Hb, TRF, and TIBC were. Furthermore, it seems more obvious among fulminant hepatitis and liver cirrhosis. CONCLUSIONS: The overload of iron may enhance the hepatocyte damage induced by HBV. Therefore, to detect serum markers of iron metabolism is helpful to evaluate curative effect and prognosis of hepatitis B.

Adolescent↗

PubMed2001

[Study of susceptibility loci located within Xp11 in attention deficit hyperactivity disorder].

OBJECTIVE: To detect the genetic relationship between monoamine oxidase(MAO) A type gene and attention deficit hyperactivity disorder(ADHD) in Chinese. METHODS: The haplotype-based haplotype relative risk(HHRR) and the transmission disequilibrium test(TDT) methods were used to analyze the genetic association and linkage in 60 ADHD children and their parents. RESULTS: In this sample were found significant association (chi(2)=4.90, P<0.05) and linkage (chi(2)=4.84, P<0.05) between the MAOCA 114bp allele and DSM-III-R-diagnosed ADHD in trios composed of father, mother and affected offspring. CONCLUSION: The above results suggested that ADHD was associated and in linkage with MAO A gene, and the susceptibility loci might reside in chromosome Xp11 for ADHD.

Attention Deficit Disorder with Hyperactivity↗

PubMed2001

[Effect of plastic film mulching on crop yield and nitrogen efficiency in semiarid areas].

The effect of plastic film mulching, water storage in soil profile before sowing, and nitrogen fertilization on crop yield and nitrogen efficiency was examined in this paper. The study site was on the cultivated lossial soil in semiarid areas with 415 mm of annual rainfall and the test crop was spring wheat, Triticum aestivum. In order to study the effect of plastic film mulching, 4 levels of mulching were designed, including mulching of 0, 30 and 60 days after sowing and mulching over the whole growing period. The results showed that increase of soil water storage, plastic film mulching and nitrogen fertilization increased crop yield significantly(alpha < 0.01), and their effect followed in the order of nitrogen fertilization > increase of water storage > plastic film mulching. The effect of mulching on crop yield varied with water storage, nitrogen fertilization and mulching periods. When the water storage was low, there was no significant difference in crop yield between mulching and no mulching, although mulching increased crop yield slightly, and the nitrogen efficiency was higher for no mulching and mulching 30 days. When the water storage was high, the difference between the yield of mulching 60 days and no mulching was significant, but no difference in nitrogen efficiency was found for mulching 30 days, 60 days and over whole growing period. It was suggested that mulching over whole growing period was of less significance in practice.

Crops, Agricultural↗

PubMed2001

[Investigation of the clinicopathologic features, immunophenotype and Epstein-Barr virus infection of primary central nervous system lymphoma].

OBJECTIVE: To investigate the clinicopathological features, immunophenotypes and EB virus infection of 25 cases of primary central nervous system lymphoma (PCNSL). METHODS: Immunohistochemical staining was performed using monoclonal antibodies, L26 (CD20), kappa,lambda for B lymphocytes, UCHL-1 (CD45RO) for T lymphocytes, CS1-4 for latent membrane protein-1 (LMP-1) and GFAP for gliocytes. In situ hybridization was used for detection of EB virus encoded small nuclear RNAs (EBER1/2). RESULTS: All of the 25 PCNSL were of B lymphocyte origin with high-grade malignancy. Only 2/25 (8%) cases showed positive signal in EBER1/2 in situ hybridization. CONCLUSION: This group of PCNSL were all B-cell lymphomas, and the role of EB virus in this group of PCNSL was uncertain.

Adolescent↗

PubMed2001

[Cloning and analyzing of the conserved protein gene in Streptococcus sanguinis ATCC10556].

OBJECTIVE: To clone and analyze the conserved protein gene in Streptococcus sanguinis(S.s) ATCC10556. METHODS: Southern blotting hybridization, molecular cloning techniques and dot blotting hybridization were employed to obtain the target clone which harbored the specific DNA fragment. The nucleotide sequence of the target clone was determined. The gene and its product were analyzed by Genework software and bioinformatics techniques. RESULTS: The conserved protein gene in Streptococcus sanguinis ATCC10556 was cloned for the first time and named as Streptococcus sanguinis conserved protein gene (Sscp gene). The Genbank accession number for Sscp gene is AY032739. The conserved protein gene in S.s ATCC10556 (named sscp163) was a transmembrane protein and contained two AAA domains. CONCLUSION: sscp163 protein might take part in the cell division in Streptococcus sanguinis; its function is similar to that of FtsK in E.coli.

Amino Acid Sequence↗

PubMed2001

Percutaneous balloon aortic valvuloplasty in the treatment of congenital valvular aortic stenosis in children.

OBJECTIVE: To assess the effect of the balloon valvuloplasty for for congenital valvular aortic stenosis (AS) in children. METHODS: A total of 27 (mean age 6.09 years) children with AS accepted the treatment of percutaneous balloon aortic valvuloplasty (PBAV). The ratios of balloon/valve were 0.95 +/- 0.08 for 19 cases of typical AS and 1.00 +/- 0.11 for 8 cases of hypoplastic AS. The patients were evaluated by the gradients across aortic valves in pre- and post-PBAV and by echocardiogram during the follow-up period. RESULTS: Fifteen of 19 (78.9%) cases of typical AS had a better outcome and the gradient of the remaining 4 cases (26.7%) had increased after follow-up (delta P > 50 mm Hg). Four of 8 (50.0%) cases of hypoplastic AS had satisfactory responses and the gradient of the remaining 3 cases (75.0%) rose. There was no moderate to severe aortic insufficiency (AI). CONCLUSION: The balloon aortic valvuloplasty provides safe and significant hemodynamic and clinical improvement in pediatric patients. The outcome of PBAV for typical AS is better than for hypoplastic AS.

Adolescent↗

PubMed2001

Percutaneous balloon angioplasty of coarctation of the aorta in children: 12-year follow-up results.

OBJECTIVE: To evaluate the efficiency of percutaneous balloon angioplasty of coarctation of the aorta in children and discuss its risk factors that can lead to poor long-term results. METHODS: From September 1987 to August 1999, 24 patients underwent 27 balloon angioplasty procedures for native or recurrent coarctation of the aorta at our institution. There were 19 patients with discrete (membranous) coarctation, 4 patients with long-segment and aortic arch hypoplasia, and 1 patient with postoperative recurrence. The balloon diameter was chosen not to exceed the diameter of the aorta proximal to the stenotic site (11.06 +/- 2.80 mm vs 11.78 +/- 3.18 mm), with the chosen diameter two to four times that of the stenotic segment (2.57 +/- 0.68 times). The patients have been followed up for half to twelve years (mean 6.2 +/- 2.8 years). Satisfactory result was defined as a reduction in the pressure gradient across the site of coarctation to < or = 20 mm Hg. RESULTS: The systolic pressure gradient across the coarctation site decreased from 48.17 +/- 14.68 mm Hg to 14.96 +/- 13.12 mm Hg (P < 0.01) and the diameter of the coarctation site increased from 4.66 +/- 2.43 mm to 8.80 +/- 3.32 mm (P < 0.01). Immediate satisfactory results were obtained in 19 patients (79%). Of the 5 patients with unsatisfactory results, 4 had aortic arch hypoplasia and 1 had membranous coarctation. Of the 19 patients with satisfactory results, 18 patients had membranous coarctation and 1 patient had recurrent postoperative coarctation. No aneurysm and other complications had occurred in any patients at the follow-ups. CONCLUSION: Percutaneous balloon angioplasty is an effective treatment alternative to surgery in most patients with recurrent postoperative or native membranous coarctation of the aorta. It should not be recommended for the coarctation of aortic arch hypoplasia.

Adolescent↗

PubMed2001

All-trans retinoic acid in pulmonary vascular structural remodeling in rats with pulmonary hypertension induced by monocrotaline.

OBJECTIVE: To determine whether all-trans retinoic acid (atRA) exerts an inhibitory effect on rats with pulmonary hypertension induced by monocrotaline. METHODS: All rats were given a single subcutaneous injection of either monocrotaline (60 mg/kg) or saline. Monocrotaline-injected rats received either atRA (30 mg.kg-1.day-1) or saline through oral-gastro intubation. On Days 7, 14, 21, and 28 respectively after monocrotaline injection, cardiovascular catheters were inserted to examine the mean pulmonary artery pressure of rats in each group. Meanwhile, the matrix metalloproteinase-1 (MMP-1) mRNA expression and hydroxyproline content in the main pulmonary artery were determined by RT-PCR and chromometry, respectively. RESULTS: The mean pulmonary artery pressure of rats in the model group increased significantly on day 21 and reached a peak on Day 28 compared with the control group (25.7 +/- 4.3 mm Hg vs 15.1 +/- 1.5 mm Hg and 38.5 +/- 6.4 mm Hg vs 16.4 +/- 2.0 mm Hg, P < 0.01). MMP-1 mRNA overexpression was present on Day 14 (0.72 +/- 0.15 vs 0.39 +/- 0.08, P < 0.01) and was rapidly down-regulated on Day 21 and 28 compared with Day 14, but was still higher than that in the control. The hydroxyoroline content of the main pulmonary artery dropped significantly on Day 14 (4.01 +/- 1.13 micrograms/mg vs 5.10 +/- 0.91 micrograms/mg, P < 0.05) and increased significantly on Days 21 and 28 compared with the control. atRA inhibited the MMP-1 mRNA overexpression from Day 14 to Day 28 and reduced the hydroxyproline content (5.59 +/- 0.70 micrograms/mg vs 7.96 +/- 1.13 micrograms/mg and 7.77 +/- 0.96 micrograms/mg vs 9.93 +/- 1.27 micrograms/mg, P < 0.01) and the mean pulmonary artery pressure compared with the model group (19.6 +/- 3.2 mm Hg vs 25.7 +/- 4.3 mm Hg and 26.3 +/- 4.6 mm Hg vs 38.5 +/- 6.4 mm Hg, P < 0.01). CONCLUSION: atRA inhibits MMP-1 overexpression and the accumulation of collagen, which might elicit favorable geometric remodeling in rat pulmonary hypertension induced by monocrotaline.

Animals↗

PubMed2001

Nested polymerase chain reaction in detection of Plasmodium vivax sporozoites in mosquitoes.

OBJECTIVE: To detect malaria DNA in mosquitoes. METHODS: A nested polymerase chain reaction (nested PCR) procedure which amplifies a 121 bp DNA of a SSUrRNA gene specific to Plasmodium vivax was used. RESULTS: In laboratory-infected mosquitoes, nested PCR could detect as few as 3 sporozoites or 1 infected mosquito mixed in a group of 99 normal ones. Furthermore, no specific 121 bp band was seen with DNA templates from other malaria parasites or negative mosquitoes. CONCLUSION: Sensitivity and specificity obtained indicated an advantage of the nested PCR over DNA probes or direct PCR for the detection of Plasmodium vivax sporozoites in mosquitoes with low-grade parasitic infections.

Animals↗

PubMed2001

[Evaluation of intraperitoneal chemotherapy in stage IV gastrointestinal cancer].

OBJECTIVE: To evaluate the short term and long term therapeutic effects of intraperitoneal versus intravenous chemotherapy in 56 cases with stage IV gastrointestinal cancer. METHODS: The patients were randomly divided into two groups: 35 cases in the intraperitoneally treated group and 21 cases in the intravenously treated group. The short term effects and side effects were observed. The survival time of the patients was also recorded. The survival function was estimated by Kaplan-Meier method, and the significance test was done by Log rank method. RESULTS: There was no significant difference between the two groups in short term effects, and liver and kidney damages. Nausea, vomiting and bone marrow suppression were more severe in the intravenously treated group, while abdominal distension and pain were the major side effects in the intraperitoneally treated group. The median survival time and one year survival rate of patients in the intraperitoneally treated group were higher than those in the intravenously treated group. CONCLUSION: For patients with stage IV gastrointestinal cancer, intraperitoneal administration of chemotherapeutic agents is a better treatment of choice.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed2001

[Estimation of insulin secretion rate in multiple sampled intravenous glucose tolerance test].

OBJECTIVE: To measure and calculate insulin secretion rate(ISR) in multiple sampled intravenous glucose tolerance test (FSIVGTT) according to the two compartment model and standard parameters of the kinetics of connecting peptide (C-P) in vivo. METHODS: 15 subjects with normal glucose tolerance and 11 type 2 diabetic patients took part in the study. Oral glucose tolerance test (OGTT) and FSIVGTT were performed. Glucose concentrations were measured by hexokinase method. Insulin (INS) and C-P concentrations were measured by radioimmunoassay. A computer procedure devised by our laboratory was used to calculate the value of ISR at each time point. RESULTS: In the control group, serum INS and C-P concentrations reached the peak at 4 min, the second peak was not obvious. In type 2 diabetes, only 5 subjects had a small peak within 4 min, two curves reached its peak between 60 and 80 min. In the control group, ISR reached its peak 2 min after injection of glucose, that was earlier than INS and C-P curves in time sequence (P = 0.000), the second obvious peak was shown at 22 min. In type 2 diabetes, an obvious but small peak of ISR was shown at 2 min and all the patients had this peak. CONCLUSIONS: It is necessary to take the process of metabolic clearance of INS and C-P into consideration, when blood concentration of INS and C-P were used as indexes to evaluate the secretion function of beta-cells. The ISR profile is more sensitive for investigation of the second phase of insulin secretion in the control group and the first phase in type 2 diabetes group.

Blood Glucose↗

PubMed2001

[Studies on the manufacture and immunogenicity of purified rabies vaccines on humans Vero cell].

OBJECTIVE: Using Vero cell as basic cultural material to improve the quality of rabies vaccines and to produce rabies vaccines for humans. METHODS: CTN-1V10 strain were used for production. Vero cell of 150th generation were used for cultivation. Rotating cultivatal method with rotating bottle was used. Fluids with virus were collected at different time. Puritied rabies vaccine was produced on Vero cell after clarification, condensation, purification and extermination. A batch of vaccines made by this techniques were used for immunological observation. Sixty-three people were injected with this rabies vaccine according to the procedure of time of exposure. Thirty of them were injected with vaccines made in France (Verorab) while the others were injected with vaccines to be tested. Side effect and neutralizing antibody were recorded. RESULTS: The quality of this newly developed rabies vaccines has met the quality set by WHO. After all dosages of injection, the rates of positive antibody were both 100% in two groups. The neutralizing antibody among testing group was 11.94 IU/ml comparing with control as 11.69 IU/ml. CONCLUSION: Purified rabies vaccines on Vero cell for humans had reasonable manufacture technique and less little effect with good technological imnunogenicity.

Animals↗

PubMed2001

[An epidemiological survey of blindness and low vision in Meixian County].

OBJECTIVE: To study the status of blindness and low vision in Meixian County. METHODS: The stratified random sampling rule and the standard grading system of blindness set by WHO were adopted in the study, and 11 327 subjects were enrolled (a sampling fraction of 2.01%) in the whole county. RESULTS: The prevalence of bilateral blindness and low vision was found to be 0.47% and 0.89%; that of monocular blindness and low vision was 0.72% and 0.59%, respectively. Subjects over 50 years old had a significantly higher prevalence of blindness and low vision. The causes leading to blindness and low vision were, in falling order, cataract, glaucoma, ametropia/amblyopia and pterygium. CONCLUSION: The treatment of cataract is the main measure to decrease the prevalence of blindness and low vision.

Adolescent↗